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1.
The Annual bioProcessUK Conference has acted as the key networking event for bioprocess scientists and engineers in the UK for the past 10 years. The following article is a report from the sessions that focused on continuous bioprocessing during the 10th Annual bioProcessUK Conference (London, December 2013). These sessions were organized by the ‘EPSRC Centre for Innovative Manufacturing in Emergent Macromolecular Therapies’ hosted at University College London. A plenary lecture and workshop provided a forum for participants to debate topical issues in roundtable discussions with industry and academic experts from institutions such as Genzyme, Janssen, Novo Nordisk, Pfizer, Merck, GE Healthcare and University College London. The aim of these particular sessions was to understand better the challenges and opportunities for continuous bioprocessing in the bioprocessing sector. 相似文献
2.
Acetate transport in the S3 segment of the rabbit proximal tubule and its effect on intracellular pH 总被引:2,自引:1,他引:1
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We monitored intracellular pH (pHi) in isolated perfused S3 segments of the rabbit proximal tubule, and studied the effect of acetate (Ac-) transport on pHi. pHi was calculated from the absorbance spectrum of 4',5'-dimethyl-5-(and 6) carboxyfluorescein trapped intracellularly. All solutions were nominally HCO3(-)-free. Removal of 10 mM Ac- from bath and lumen caused pHi to rapidly rise by approximately 0.2, and then to decline more slowly to a value approximately 0.35 below the initial one. Removal of only luminal Ac- caused pHi changes very similar to those resulting from bilateral removal of Ac-. When Ac- was removed from bath only, pHi rose rapidly at first, and then continued to rise more slowly. Readdition of Ac- to bath caused pHi to rapidly fall to a value slightly higher than the one prevailing before the removal of Ac- from the bath. In experiments in which Ac- was first removed from both bath and lumen, readdition of 10 mM Ac- to only lumen caused a rapid but small acidification, followed by a slower alkalinization that brought the pHi near the value that prevailed before the bilateral removal of Ac-. The alkalinizing effects caused by the readdition of 10 or 0.5 mM Ac- were indistinguishable. When Ac- was returned to only lumen in the absence of luminal Na+, there was a small and rapid pHi decrease, but no pHi recovery. Removal of Na+ from bath did not affect the pHi transients caused by the addition of Ac- to lumen. In experiments in which Ac- was first removed bilaterally, readdition of Ac- to only bath caused a large and sustained drop in pHi, whereas the subsequent removal of Ac- from the bath caused a slight alkalinization. These pHi changes caused by readdition or removal of Ac- from baths were unaffected by the absence of external Na+. We conclude that there is a Na+/Ac- cotransporter at the luminal membrane, and pathways for acetic acid transport at both luminal and basolateral membranes. The net effect of Ac- transport on pHi is to alkalinize the cell as a result of the luminal entry of Na+/Ac-, which is followed by the luminal and basolateral exit of acetic acid. 相似文献
3.
Inbreeding under a cyclical mating system 总被引:1,自引:0,他引:1
A. Farid M. Makarechian C. Strobeck 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(4):506-515
Summary General recursion formulae for the coefficient of inbreeding under a cyclical mating system were derived in which one male and one female are selected from each of the n families per generation (population size N = 2 n). Each male is given the family number of his sire in each generation, while his mate comes from another family, varying systematically in different generations. Males of the r-th family in generations 1, 2, 3,..., t = n–1 within each cycle mate with females from families r+1, r+2, r+3,..., r+t to produce generations 2, 3, 4,..., t+1=1, respectively. The change in heterozygosity shows a cyclical pattern of rises and falls, repeating in cycles of n–1 generations. The rate of inbreeding oscillates between <-3% to >6% in different generations within each cycle, irrespective of the population size. The average rate of inbreeding per generation is approximately 1/[4 N-(Log2N+1)], which is the rate for the maximum avoidance of inbreeding. The average inbreeding effective population size is approximately 2 N–2. 相似文献
4.
TSH is a heterodimeric glycoprotein hormone, whose dissociated subunits are without biological activity. This has precluded the assessment of the relative contribution of each subunit to hormone action. We have raised anti-idiotypes to monoclonal antibodies specific, respectively, for the alpha and beta hTSH subunits. The anti-beta anti-idiotype inhibited 125I-hTSH binding to the beta subunit-specific monoclonal quantitatively, whereas 125I-hTSH binding to the alpha subunit-specific monoclonal was not inhibited by anti-alpha anti-idiotypes, suggesting that only the former is an "internal image" anti-idiotype. Neither of the two anti-idiotypes nor equimolar mixtures thereof inhibited 125I-bTSH binding to thyroid membranes, even though radiolabelled anti-idiotypes showed saturable binding to thyroid plasma membrane which was inhibited 41-65% by bTSH. Each anti-idiotype alone caused 9% inhibition (compared to 50% by NRIgG) of thyroid plasma membrane adenylate cyclase. Equimolar mixtures (125 micrograms/ml IgG of each anti-idiotype) induced enzyme activity equivalent to 85% of that of 250 mU/ml of TSH. The TSH-like action of the two anti-idiotypes was also reflected in their capacity to increase (450% by 250 micrograms/ml IgG compared to normal rabbit IgG) the uptake of 131I into isolated thyrocytes and to promote the organization of such cells into follicular structures. At 250 micrograms/ml, anti-beta anti-idiotype promoted the organization of small follicles and only at a concentration of 500 micrograms/ml did it enhance 131I uptake. 相似文献
5.
6.
Dot-enzyme-linked immunosorbent assay (dot-ELISA) for the rapid diagnosis of human fascioliasis 总被引:1,自引:0,他引:1
H I Shaheen K A Kamal Z Farid N Mansour F N Boctor J N Woody 《The Journal of parasitology》1989,75(4):549-552
A dot-enzyme-linked immunosorbent assay (dot-ELISA) was developed as a fast and field applicable antibody detection tool for the diagnosis of human fascioliasis. The assay is performed using partially purified antigens from a species of Fasciola at 180 ng protein/dot (2 microliters) and serum samples at 1:20 dilution (1 microliter). Dot-ELISA results completely agreed with those of micro-ELISA. Antigen-coated nitrocellulose sheets stored for 3 mo at -20 C showed results identical to fresh sheets. Sera from patients with fascioliasis (n = 30) and other parasitic or viral infections (n = 120) were compared with sera from healthy controls (n = 14). Ninety samples can be tested within 90 min. The sensitivity, specificity, and speed of the assay may justify its use in laboratory and field studies. 相似文献
7.
E. M. Petty J. S. Green S. J. Marx R. T. Taggart N. Farid A. E. Bale 《American journal of human genetics》1994,54(6):1060-1066
An autosomal dominant syndrome of prolactinomas, carcinoids, and hyperparathyroidism was described in four Newfoundland kindreds in 1980 and in one kindred from the Pacific Northwest in 1983. Because this syndrome shares many features with multiple endocrine neoplasia type 1, the gene for which maps to proximal chromosome 11q, we performed linkage studies with chromosome 11 markers in prolactinoma families to determine whether the two genes map to the same location. All proximal chromosome 11q markers gave positive LOD scores, and no recombinants were seen with PYGM (LOD score 15.25, recombination fraction .0). All affected individuals from Newfoundland shared the same PYGM allele, providing evidence for a founder effect. The disease in the Pacific Northwest kindred cosegregated with a different PYGM allele. 相似文献
8.
Farid M. Ibatullin Alexander M. Golubev Leonid M. Firsov Kirill N. Neustroev 《Glycoconjugate journal》1993,10(3):214-218
The present work investigated the possibility of cleavage of -linkages between mannose or galactose and serine/threonine residues by -mannosidase and -galactosidase. The study was carried out initially with model synthetic compounds imitating theO-glycosidic bond in glycoproteins, and further with glucoamylase. It was shown that -mannosidase and -galactosidase can hydrolyse these linkages after proteolytic digestion of glucosamylase. 相似文献
9.
Amir Hamza Khan Dr. Said Hassan Muhammad Aamir Dr. Muhammad Waseem Khan Dr. Fazal Haq Junaid Hayat Dr. Muhammad Rizwan Dr. Amin Ullah Izzat Ullah Dr. Gokhan Zengin Dr. Arshad Farid 《化学与生物多样性》2023,20(10):e202301068
The current study was designed to evaluate the antioxidant, anticancer and antimicrobial activities of silver nanoparticles (AgNPs) biosynthesized by Spirulina platensis extract. The biosynthesized silver nanoparticles were characterized using Fourier transform infrared (FT-IR) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The antioxidant activity of the biosynthesized AgNPs were determined via DPPH radical scavenging assay while its anticancer activity was determined using the MTT assay. The antimicrobial activity of the biosynthesized AgNPs were analyzed by disc diffusion method. Spirulina platensis acts as a reducing and capping agent. The efficacy of silver nanoparticles (AgNPs) in inhibiting the growth of Gram-negative bacteria, specifically Acetobacter, Klebsiella, Proteus vulgaris, and Pseudomonas aeruginosa, was assessed by the utilisation of the diffusion method. The study aimed to evaluate the efficacy of biosynthesized silver nanoparticles (AgNPs) against many strains of Pseudomonas aeruginosa bacteria. The findings of the study revealed that when administered in doses of 50 μl, 75 μl, and 100 μl, the largest observed zone of inhibition corresponded to measurements of 10.5 mm, 14 mm, and 16 mm, respectively. A zone of inhibition with dimensions of 8 mm, 10.5 mm, and 12 mm was detected during testing against Acetobacter at concentrations of 50 μl, 75 μl, and 100 μl, respectively. The findings also indicate that there is a positive correlation between the concentration of AgNP and the DPPH scavenging ability of silver nanoparticles. The percentage of inhibition observed at concentrations of 500 μg/ml, 400 μg/ml, 300 μg/ml, 200 μg/ml, and 100 μg/ml were recorded as 80±1.98, 61±1.98, 52±1.5, 42±1.99, and 36±1.97, respectively. In addition, it was observed that the silver nanoparticles exhibited the greatest antioxidant activity at a concentration of 500 g/ml, with a measured value of 80.89±1.99. The IC-50 values, representing the inhibitory concentration required to achieve 50 % inhibition, were found to be 8.16, 19.15, 30.14, 41.13, and 63.11 at inhibition levels of 36±1.97, 42±1.99, 52±1.5, 61±1.98, and 80±1.98, respectively. 相似文献
10.